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- /*
- * Copyright 2015 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
- #include "src/pathops/SkPathOpsBounds.h"
- #include "src/pathops/SkPathOpsCurve.h"
- #include "src/pathops/SkPathOpsRect.h"
- // this cheats and assumes that the perpendicular to the point is the closest ray to the curve
- // this case (where the line and the curve are nearly coincident) may be the only case that counts
- double SkDCurve::nearPoint(SkPath::Verb verb, const SkDPoint& xy, const SkDPoint& opp) const {
- int count = SkPathOpsVerbToPoints(verb);
- double minX = fCubic.fPts[0].fX;
- double maxX = minX;
- for (int index = 1; index <= count; ++index) {
- minX = SkTMin(minX, fCubic.fPts[index].fX);
- maxX = SkTMax(maxX, fCubic.fPts[index].fX);
- }
- if (!AlmostBetweenUlps(minX, xy.fX, maxX)) {
- return -1;
- }
- double minY = fCubic.fPts[0].fY;
- double maxY = minY;
- for (int index = 1; index <= count; ++index) {
- minY = SkTMin(minY, fCubic.fPts[index].fY);
- maxY = SkTMax(maxY, fCubic.fPts[index].fY);
- }
- if (!AlmostBetweenUlps(minY, xy.fY, maxY)) {
- return -1;
- }
- SkIntersections i;
- SkDLine perp = {{ xy, { xy.fX + opp.fY - xy.fY, xy.fY + xy.fX - opp.fX }}};
- (*CurveDIntersectRay[verb])(*this, perp, &i);
- int minIndex = -1;
- double minDist = FLT_MAX;
- for (int index = 0; index < i.used(); ++index) {
- double dist = xy.distance(i.pt(index));
- if (minDist > dist) {
- minDist = dist;
- minIndex = index;
- }
- }
- if (minIndex < 0) {
- return -1;
- }
- double largest = SkTMax(SkTMax(maxX, maxY), -SkTMin(minX, minY));
- if (!AlmostEqualUlps_Pin(largest, largest + minDist)) { // is distance within ULPS tolerance?
- return -1;
- }
- return SkPinT(i[0][minIndex]);
- }
- void SkDCurve::offset(SkPath::Verb verb, const SkDVector& off) {
- int count = SkPathOpsVerbToPoints(verb);
- for (int index = 0; index <= count; ++index) {
- fCubic.fPts[index] += off;
- }
- }
- void SkDCurve::setConicBounds(const SkPoint curve[3], SkScalar curveWeight,
- double tStart, double tEnd, SkPathOpsBounds* bounds) {
- SkDConic dCurve;
- dCurve.set(curve, curveWeight);
- SkDRect dRect;
- dRect.setBounds(dCurve, fConic, tStart, tEnd);
- bounds->set(SkDoubleToScalar(dRect.fLeft), SkDoubleToScalar(dRect.fTop),
- SkDoubleToScalar(dRect.fRight), SkDoubleToScalar(dRect.fBottom));
- }
- void SkDCurve::setCubicBounds(const SkPoint curve[4], SkScalar ,
- double tStart, double tEnd, SkPathOpsBounds* bounds) {
- SkDCubic dCurve;
- dCurve.set(curve);
- SkDRect dRect;
- dRect.setBounds(dCurve, fCubic, tStart, tEnd);
- bounds->set(SkDoubleToScalar(dRect.fLeft), SkDoubleToScalar(dRect.fTop),
- SkDoubleToScalar(dRect.fRight), SkDoubleToScalar(dRect.fBottom));
- }
- void SkDCurve::setQuadBounds(const SkPoint curve[3], SkScalar ,
- double tStart, double tEnd, SkPathOpsBounds* bounds) {
- SkDQuad dCurve;
- dCurve.set(curve);
- SkDRect dRect;
- dRect.setBounds(dCurve, fQuad, tStart, tEnd);
- bounds->set(SkDoubleToScalar(dRect.fLeft), SkDoubleToScalar(dRect.fTop),
- SkDoubleToScalar(dRect.fRight), SkDoubleToScalar(dRect.fBottom));
- }
- void SkDCurveSweep::setCurveHullSweep(SkPath::Verb verb) {
- fOrdered = true;
- fSweep[0] = fCurve[1] - fCurve[0];
- if (SkPath::kLine_Verb == verb) {
- fSweep[1] = fSweep[0];
- fIsCurve = false;
- return;
- }
- fSweep[1] = fCurve[2] - fCurve[0];
- // OPTIMIZE: I do the following float check a lot -- probably need a
- // central place for this val-is-small-compared-to-curve check
- double maxVal = 0;
- for (int index = 0; index <= SkPathOpsVerbToPoints(verb); ++index) {
- maxVal = SkTMax(maxVal, SkTMax(SkTAbs(fCurve[index].fX),
- SkTAbs(fCurve[index].fY)));
- }
- {
- if (SkPath::kCubic_Verb != verb) {
- if (roughly_zero_when_compared_to(fSweep[0].fX, maxVal)
- && roughly_zero_when_compared_to(fSweep[0].fY, maxVal)) {
- fSweep[0] = fSweep[1];
- }
- goto setIsCurve;
- }
- SkDVector thirdSweep = fCurve[3] - fCurve[0];
- if (fSweep[0].fX == 0 && fSweep[0].fY == 0) {
- fSweep[0] = fSweep[1];
- fSweep[1] = thirdSweep;
- if (roughly_zero_when_compared_to(fSweep[0].fX, maxVal)
- && roughly_zero_when_compared_to(fSweep[0].fY, maxVal)) {
- fSweep[0] = fSweep[1];
- fCurve[1] = fCurve[3];
- }
- goto setIsCurve;
- }
- double s1x3 = fSweep[0].crossCheck(thirdSweep);
- double s3x2 = thirdSweep.crossCheck(fSweep[1]);
- if (s1x3 * s3x2 >= 0) { // if third vector is on or between first two vectors
- goto setIsCurve;
- }
- double s2x1 = fSweep[1].crossCheck(fSweep[0]);
- // FIXME: If the sweep of the cubic is greater than 180 degrees, we're in trouble
- // probably such wide sweeps should be artificially subdivided earlier so that never happens
- SkASSERT(s1x3 * s2x1 < 0 || s1x3 * s3x2 < 0);
- if (s3x2 * s2x1 < 0) {
- SkASSERT(s2x1 * s1x3 > 0);
- fSweep[0] = fSweep[1];
- fOrdered = false;
- }
- fSweep[1] = thirdSweep;
- }
- setIsCurve:
- fIsCurve = fSweep[0].crossCheck(fSweep[1]) != 0;
- }
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